return在try块里作用范围

以下程序输出结果是30

程序走try块里累加10，并没有返回值（跳过了try块里的return），而直接走finally块里累加10，而后返回结果

public class Demo{public static void main(String args[]){int num = 10;System.out.println(test(num));}public static int test(int b){try{b += 10;return b;}catch(RuntimeException e){}catch(Exception e2){}finally{b += 10;return b;}}}

注释掉finally里的return 程序直接报错

public class Demo{public static void main(String args[]){int num = 10;System.out.println(test(num));}public static int test(int b){try{b += 10;return b;}catch(RuntimeException e){}catch(Exception e2){}finally{b += 10;//return b;}}}

以下程序都没执行try里的return

public class Demo{public static void main(String args[]){int num = 10;System.out.println(test1(num));System.out.println(test2());System.out.println(test3().toString());}public static int test1(int b){try{b += 10;return b;}catch(RuntimeException e){}catch(Exception e2){}finally{b += 10;return b;}}public static String test2(){    String test = "111";    try {        test = "222";        return test;    } catch( Exception e) {    } finally {        test = "333";        return test;    }}public static StringBuffer test3(){    StringBuffer test = new StringBuffer();    try {        test.append("123");        return test;    } catch( Exception e) {    } finally {        test.append("456");        return test;    }}}

运行结果：

30 

333

123456